Damnit, the lipo battery industry needs better standards!
11-10-2009, 05:40 PM
#26
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RE: Damnit, the lipo battery industry needs better standards!
Here's a quote from elsewhere...
“HK (Zippy) works with factories over there to purchase all their “old stock” lipos. Basically they buy the cells/packs that have been sitting on the shelves for several years. They buy them in bulk at a very heavy discount because the factories are trying to unload them and can not sell them to any reputable companies. They also will take all of the ding/damaged/low voltage cells. They send the packs out without paying any import duties here to the USA by laying on the import documents and calling them a gift. Therefore, shafting the American tax payer and getting a tax dodging advantage on the US Companies…”
Don't know if its true, but it does ring a bit of a bell. There is always a markup the more hands a product goes through (true whether you are here, in Europe, etc). But there also is a reason that this company can sell stuff with such a large delta in price. It would be nice if all sellers of any Lithum batteries were more forthcoming with exactly what cells are in their batteries, ala with the NiCd and NiMH world (its not perfect there either, but still).
Good luck with customer support; but otherwise they are probably good for throwaway batteries as long as they don't burn out an ESC or motor.
“HK (Zippy) works with factories over there to purchase all their “old stock” lipos. Basically they buy the cells/packs that have been sitting on the shelves for several years. They buy them in bulk at a very heavy discount because the factories are trying to unload them and can not sell them to any reputable companies. They also will take all of the ding/damaged/low voltage cells. They send the packs out without paying any import duties here to the USA by laying on the import documents and calling them a gift. Therefore, shafting the American tax payer and getting a tax dodging advantage on the US Companies…”
Don't know if its true, but it does ring a bit of a bell. There is always a markup the more hands a product goes through (true whether you are here, in Europe, etc). But there also is a reason that this company can sell stuff with such a large delta in price. It would be nice if all sellers of any Lithum batteries were more forthcoming with exactly what cells are in their batteries, ala with the NiCd and NiMH world (its not perfect there either, but still).
Good luck with customer support; but otherwise they are probably good for throwaway batteries as long as they don't burn out an ESC or motor.
ORIGINAL: samguan
Try hobbycity and you will love both the quality and the price! Search around and you will find tons of information and comments on HobbyCity.
Try hobbycity and you will love both the quality and the price! Search around and you will find tons of information and comments on HobbyCity.
11-10-2009, 06:19 PM
#27
RE: Damnit, the lipo battery industry needs better standards!
[quote]ORIGINAL: thzero
Here's a quote from elsewhere...
“HK (Zippy) works with factories over there to purchase all their “old stock” lipos. Basically they buy the cells/packs that have been sitting on the shelves for several years. They buy them in bulk at a very heavy discount because the factories are trying to unload them and can not sell them to any reputable companies. They also will take all of the ding/damaged/low voltage cells. They send the packs out without paying any import duties here to the USA by laying on the import documents and calling them a gift. Therefore, shafting the American tax payer and getting a tax dodging advantage on the US Companies…”
Don't know if its true, but it does ring a bit of a bell. There is always a markup the more hands a product goes through (true whether you are here, in Europe, etc). But there also is a reason that this company can sell stuff with such a large delta in price. It would be nice if all sellers of any Lithum batteries were more forthcoming with exactly what cells are in their batteries, ala with the NiCd and NiMH world (its not perfect there either, but still).
Good luck with customer support; but otherwise they are probably good for throwaway batteries as long as they don't burn out an ESC or motor.
[/quote
Sounds and smells like BS to me.
Here's a quote from elsewhere...
“HK (Zippy) works with factories over there to purchase all their “old stock” lipos. Basically they buy the cells/packs that have been sitting on the shelves for several years. They buy them in bulk at a very heavy discount because the factories are trying to unload them and can not sell them to any reputable companies. They also will take all of the ding/damaged/low voltage cells. They send the packs out without paying any import duties here to the USA by laying on the import documents and calling them a gift. Therefore, shafting the American tax payer and getting a tax dodging advantage on the US Companies…”
Don't know if its true, but it does ring a bit of a bell. There is always a markup the more hands a product goes through (true whether you are here, in Europe, etc). But there also is a reason that this company can sell stuff with such a large delta in price. It would be nice if all sellers of any Lithum batteries were more forthcoming with exactly what cells are in their batteries, ala with the NiCd and NiMH world (its not perfect there either, but still).
Good luck with customer support; but otherwise they are probably good for throwaway batteries as long as they don't burn out an ESC or motor.
ORIGINAL: samguan
Try hobbycity and you will love both the quality and the price! Search around and you will find tons of information and comments on HobbyCity.
Try hobbycity and you will love both the quality and the price! Search around and you will find tons of information and comments on HobbyCity.
Sounds and smells like BS to me.
11-10-2009, 06:21 PM
#28
Senior Member
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RE: Damnit, the lipo battery industry needs better standards!
ORIGINAL: thzero
Here's a quote from elsewhere...
“HK (Zippy) works with factories over there to purchase all their “old stock” lipos. Basically they buy the cells/packs that have been sitting on the shelves for several years. They buy them in bulk at a very heavy discount because the factories are trying to unload them and can not sell them to any reputable companies. They also will take all of the ding/damaged/low voltage cells. They send the packs out without paying any import duties here to the USA by laying on the import documents and calling them a gift. Therefore, shafting the American tax payer and getting a tax dodging advantage on the US Companies…”
Don't know if its true, but it does ring a bit of a bell. There is always a markup the more hands a product goes through (true whether you are here, in Europe, etc). But there also is a reason that this company can sell stuff with such a large delta in price. It would be nice if all sellers of any Lithum batteries were more forthcoming with exactly what cells are in their batteries, ala with the NiCd and NiMH world (its not perfect there either, but still).
Good luck with customer support; but otherwise they are probably good for throwaway batteries as long as they don't burn out an ESC or motor.
Here's a quote from elsewhere...
“HK (Zippy) works with factories over there to purchase all their “old stock” lipos. Basically they buy the cells/packs that have been sitting on the shelves for several years. They buy them in bulk at a very heavy discount because the factories are trying to unload them and can not sell them to any reputable companies. They also will take all of the ding/damaged/low voltage cells. They send the packs out without paying any import duties here to the USA by laying on the import documents and calling them a gift. Therefore, shafting the American tax payer and getting a tax dodging advantage on the US Companies…”
Don't know if its true, but it does ring a bit of a bell. There is always a markup the more hands a product goes through (true whether you are here, in Europe, etc). But there also is a reason that this company can sell stuff with such a large delta in price. It would be nice if all sellers of any Lithum batteries were more forthcoming with exactly what cells are in their batteries, ala with the NiCd and NiMH world (its not perfect there either, but still).
Good luck with customer support; but otherwise they are probably good for throwaway batteries as long as they don't burn out an ESC or motor.
ORIGINAL: samguan
Try hobbycity and you will love both the quality and the price! Search around and you will find tons of information and comments on HobbyCity.
Try hobbycity and you will love both the quality and the price! Search around and you will find tons of information and comments on HobbyCity.
11-10-2009, 06:30 PM
#29
RE: Damnit, the lipo battery industry needs better standards!
ORIGINAL: t9dragon
I have heard the same thing from the owner of my LHS.
ORIGINAL: thzero
Here's a quote from elsewhere...
“HK (Zippy) works with factories over there to purchase all their “old stock” lipos. Basically they buy the cells/packs that have been sitting on the shelves for several years. They buy them in bulk at a very heavy discount because the factories are trying to unload them and can not sell them to any reputable companies. They also will take all of the ding/damaged/low voltage cells. They send the packs out without paying any import duties here to the USA by laying on the import documents and calling them a gift. Therefore, shafting the American tax payer and getting a tax dodging advantage on the US Companies…”
Don't know if its true, but it does ring a bit of a bell. There is always a markup the more hands a product goes through (true whether you are here, in Europe, etc). But there also is a reason that this company can sell stuff with such a large delta in price. It would be nice if all sellers of any Lithum batteries were more forthcoming with exactly what cells are in their batteries, ala with the NiCd and NiMH world (its not perfect there either, but still).
Good luck with customer support; but otherwise they are probably good for throwaway batteries as long as they don't burn out an ESC or motor.
Here's a quote from elsewhere...
“HK (Zippy) works with factories over there to purchase all their “old stock” lipos. Basically they buy the cells/packs that have been sitting on the shelves for several years. They buy them in bulk at a very heavy discount because the factories are trying to unload them and can not sell them to any reputable companies. They also will take all of the ding/damaged/low voltage cells. They send the packs out without paying any import duties here to the USA by laying on the import documents and calling them a gift. Therefore, shafting the American tax payer and getting a tax dodging advantage on the US Companies…”
Don't know if its true, but it does ring a bit of a bell. There is always a markup the more hands a product goes through (true whether you are here, in Europe, etc). But there also is a reason that this company can sell stuff with such a large delta in price. It would be nice if all sellers of any Lithum batteries were more forthcoming with exactly what cells are in their batteries, ala with the NiCd and NiMH world (its not perfect there either, but still).
Good luck with customer support; but otherwise they are probably good for throwaway batteries as long as they don't burn out an ESC or motor.
ORIGINAL: samguan
Try hobbycity and you will love both the quality and the price! Search around and you will find tons of information and comments on HobbyCity.
Try hobbycity and you will love both the quality and the price! Search around and you will find tons of information and comments on HobbyCity.
That is were I also heard a story like that too, untill a few guys starting showing up with Turnigy 5000 MAH pscks for $19.95 and kicking everyones arse.
Now he says that he could not make any money on them. I told him that's the whole idea.
11-10-2009, 06:47 PM
#30
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RE: Damnit, the lipo battery industry needs better standards!
ORIGINAL: Anomie
Whenever someone has a problem and comes here to share or seek help, the 'versus' begins. This is unnecessary and unwanted.
Please keep the smartass comments out and attempt to remain constructive.
Thank you.
Whenever someone has a problem and comes here to share or seek help, the 'versus' begins. This is unnecessary and unwanted.
Please keep the smartass comments out and attempt to remain constructive.
Thank you.
11-10-2009, 07:00 PM
#31
Senior Member
RE: Damnit, the lipo battery industry needs better standards!
Get a charger with a store mode-it will only charge them a minimum amount. Charge them up in store mode and you'll be ok for long term storage.
Now I have heard that you can leave lipos fully charged for up to a few days max, but that may depend on the cell itself obviously. I have left some of my Zippy packs fully charged for a couple of weeks at a time (on accident) a few times when I've been out of town, and they were fine then and now. Anyways, I now use the store feature of my Hyperion charger because I find myself driving my truck less and less as the weather gets colder and don't want to leave all of my packs at a full charge because it may be weeks or months before they get used again.
Good luck with those SMCs man, and I do agree that the RC industry needs to "standardize" lipo technology. Also, be careful discharging those lipos....go too far and you will ruin a pack.
Now I have heard that you can leave lipos fully charged for up to a few days max, but that may depend on the cell itself obviously. I have left some of my Zippy packs fully charged for a couple of weeks at a time (on accident) a few times when I've been out of town, and they were fine then and now. Anyways, I now use the store feature of my Hyperion charger because I find myself driving my truck less and less as the weather gets colder and don't want to leave all of my packs at a full charge because it may be weeks or months before they get used again.
Good luck with those SMCs man, and I do agree that the RC industry needs to "standardize" lipo technology. Also, be careful discharging those lipos....go too far and you will ruin a pack.
11-10-2009, 07:24 PM
#32
Senior Member
RE: Damnit, the lipo battery industry needs better standards!
ORIGINAL: HerrSavage
Just curious - everybody knows a well running lipo brushless is faster than nitro..
Take, say, a Savage XL with LRP Spec 3, and put it up against a Flux with Nimh. How would they compare?
Just curious..
Just curious - everybody knows a well running lipo brushless is faster than nitro..
Take, say, a Savage XL with LRP Spec 3, and put it up against a Flux with Nimh. How would they compare?
Just curious..
11-10-2009, 07:30 PM
#33
Senior Member
RE: Damnit, the lipo battery industry needs better standards!
ORIGINAL: samguan
Try hobbycity and you will love both the quality and the price! Search around and you will find tons of information and comments on HobbyCity.
My friend runs hobbycity lipos in his flux for more than 6 months now and it is a beast! Crazy power.
Try hobbycity and you will love both the quality and the price! Search around and you will find tons of information and comments on HobbyCity.
My friend runs hobbycity lipos in his flux for more than 6 months now and it is a beast! Crazy power.
11-10-2009, 07:31 PM
#34
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RE: Damnit, the lipo battery industry needs better standards!
I dont run cars, but I turn my head to lipo's due to their inherant dangers. I have a 100 year old wood framed house that will burn to a crisp if one goes up on me. I just rather not take the chance of making a mistake. I only run lipo's on my Foamy airplanes and they are 240mah 2c packs that are as big as two dimes, and those even get charged in the hole of two cinder blocks with a brick on top.
I am moving to A123's for all my large scale planes for a few reasons.
Safe
6.6 volts out of 2cell pack.
Enormous amperage spikes
Holds 6.6v all the way to the end of the pack, no declining voltage as used through out the day. Can take a 10amp charge like a champ so If you run low, you charge the pack at the field in less the 10 minutes with no worries of blowing it up.
No need for Regualtors (Applies to fueled Heli's and airplanes)
They are heavier then Lipo's, but a 3 cell back is 3300mah 9.9v's that can be charged in less then 20 minutes from a dead pack...
I am moving to A123's for all my large scale planes for a few reasons.
Safe
6.6 volts out of 2cell pack.
Enormous amperage spikes
Holds 6.6v all the way to the end of the pack, no declining voltage as used through out the day. Can take a 10amp charge like a champ so If you run low, you charge the pack at the field in less the 10 minutes with no worries of blowing it up.
No need for Regualtors (Applies to fueled Heli's and airplanes)
They are heavier then Lipo's, but a 3 cell back is 3300mah 9.9v's that can be charged in less then 20 minutes from a dead pack...
11-10-2009, 07:43 PM
#35
Senior Member
RE: Damnit, the lipo battery industry needs better standards!
I'll come out and say it-Lipos are really only as safe as the people using or charging them. The easiest way to start a fire is to overcharge/improperly charge them. Next easiest way is to short them when soldering on connectors or puncturing the pack for whatever reason. How to avoid this stuff? Get a lipo charger that has a auto mode or input verification mode-most all do now. That way you cannot overcharge or improperly charge them. If you don't have one of these chargers, always double check your inputs...make sure your pack info you have entered into the charger is right for the packs you are charging. Additionally, you should charge at 1A per 1000mah of battery capacity. That means 4.0A for a 4000mah pack, 3.5A for a 3500mah pack. As far as shorting and punctures, treat your lipos with more respect than say your typical nimh stick pack and pay attention when soldering on connectors-don't let the pos and neg wires touch. You could also run hardcased lipos because they are a bit more durable than soft cased lipos. With that said, I have hundreds of lipo cycles under my belt without any issues whatsoever and plan on hundreds more without any issues. Just folllow the "rules" of lipo and you'll be ok.
11-10-2009, 07:55 PM
#36
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RE: Damnit, the lipo battery industry needs better standards!
ORIGINAL: black mamba
I'll come out and say it-Lipos are really only as safe as the people using or charging them. The easiest way to start a fire is to overcharge/improperly charge them. Next easiest way is to short them when soldering on connectors or puncturing the pack for whatever reason. How to avoid this stuff? Get a lipo charger that has a auto mode or input verification mode-most all do now. That way you cannot overcharge or improperly charge them. If you don't have one of these chargers, always double check your inputs...make sure your pack info you have entered into the charger is right for the packs you are charging. Additionally, you should charge at 1A per 1000mah of battery capacity. That means 4.0A for a 4000mah pack, 3.5A for a 3500mah pack. As far as shorting and punctures, treat your lipos with more respect than say your typical nimh stick pack and pay attention when soldering on connectors-don't let the pos and neg wires touch. You could also run hardcased lipos because they are a bit more durable than soft cased lipos. With that said, I have hundreds of lipo cycles under my belt without any issues whatsoever and plan on hundreds more without any issues. Just folllow the ''rules'' of lipo and you'll be ok.
I'll come out and say it-Lipos are really only as safe as the people using or charging them. The easiest way to start a fire is to overcharge/improperly charge them. Next easiest way is to short them when soldering on connectors or puncturing the pack for whatever reason. How to avoid this stuff? Get a lipo charger that has a auto mode or input verification mode-most all do now. That way you cannot overcharge or improperly charge them. If you don't have one of these chargers, always double check your inputs...make sure your pack info you have entered into the charger is right for the packs you are charging. Additionally, you should charge at 1A per 1000mah of battery capacity. That means 4.0A for a 4000mah pack, 3.5A for a 3500mah pack. As far as shorting and punctures, treat your lipos with more respect than say your typical nimh stick pack and pay attention when soldering on connectors-don't let the pos and neg wires touch. You could also run hardcased lipos because they are a bit more durable than soft cased lipos. With that said, I have hundreds of lipo cycles under my belt without any issues whatsoever and plan on hundreds more without any issues. Just folllow the ''rules'' of lipo and you'll be ok.
I just rather not take the chance of making a mistake
But also I have seen a lipo go boom on a triton that only allows a 1c charge and will cut at a high voltage reading or the mah set..
The inherant danger of lipo's scare me... I dont like flames.
11-10-2009, 08:18 PM
#37
Senior Member
RE: Damnit, the lipo battery industry needs better standards!
Somebody has already gone through the trouble of typing what I was about to....enjoy. http://hpiblitzforum.com/showthread.php?t=148
"LiPo battery packs guide and warnings
First off LiPo batteries are fantastic if taken care of properly. The power to size and weight ratio is what makes these so desirable. Just a bit of info to help with LiPo selection and usage.
Discharging LiPo Batteries:
Limit LiPo Discharge to Rate or potential hazard happens when lithium polymer batteries are discharged too fast. If they do so they could potentially catch fire and burst. LiPo batteries are rated with a continuous and max discharge rating.
For example a 1500mAh LiPo may be rated at 10C continuous current should not be discharged at more than 1500mAh (1500mA * 10C * .001 = 15A) of current.
Many Lipo Packs also have a "Burst" rating. For a brief period of time you can draw more current from many LiPo packs. This "Burst" current is usually limited for around 10 seconds. The current is calculated the same way.
Another example would be a 5000mAh Lipo rated at 35C continuous current and burst of 50C for 10 seconds.
(5000mAh *35C * .001 = 175A continuous draw)
(5000mAh *50C * .001 = 250A draw for 10 seconds)
LiPo Minimum Voltage:
A very important consideration is to NOT allow the battery voltage to drop too low. The amount that the battery voltage can drop is dependent on your system. If you are using a 3-cell lithium polymer pack, you should stop use of it when voltage drops under 9 volts. If the battery voltage drops below 8 volts the batteries could become permanently damaged. Follow manufacturers recommended guidelines.
If this is unknown, a good rule to use is 3V per cell.
LiPo Maximum Temperature:
Lithium polymer batteries should not be operated in temperatures exceeding 140 degrees Fahrenheit. In the event of a crash, lithium polymer batteries should be carefully inspected for any punctures, puffiness of the batteries, or short circuits. If any of exists, do not use the batteries. Dispose of them properly. Also, NEVER store / charge lithium polymer batteries in your car – Unless you hate your car. Batteries can and do explode, and if this happens inside a vehicle the result is usually catastrophic. On a hot day, temperatures can rise inside the car and cause stored packs to rupture.
Damaged LiPo Symptoms:
• Charger does not allow the battery to charge
• Batteries are puffy to the touch (do not use!)
• Punctures in the battery cell
• Short circuits
Properly LiPo Dispose Procedure:
• Discharge all cells to the recommend cut off voltage of 3 Volts per cell
• Place in salt water for several hours
• Apply tape to one of the terminals and dispose of in the trash.
• DO NOT INCINERATE
Parallel Battery Configuration:
Use Equally Charged LiPo’s in Parallel Configurations. Battery configurations require the parallel connection of two or more Lithium Polymer (LiPo) batteries. In this case, LiPo batteries must have the same or very similar output voltage. WARNING Parallel connection of two batteries of significantly different output voltage (one is more fully charged than the other) will cause one battery to discharge into the other battery at a high current rate. This may cause damage to either of the batteries and potentially cause fire or the battery to burst. It is strongly recommended that in applications requiring parallel connection of LiPo batteries, only batteries of equivalent technology, capacity, cell count, and output voltage be used. A good assumption is that fully charged LiPo batteries of the same type are safe to connect in parallel. Unless you are certain of the proper way to connect batteries in Series or Parallel, NEVER CONNECT LIPO PACKS TOGETHER.
LiPo Cell configuration:
There are several styles, sizes and combination that are available. Most are found in a series or series parallel configuration. What ever the configuration the # of cells * 3.7v per cell = Pack voltage
Example a 3S (3 cell) * 3.7v per cell = 11.1 volts
1s= 3.7v
2s= 7.4v
3s= 11.1v
4s= 14.8v
5s= 18.5v
6s= 22.2v
7s= 25.9v
8s= 29.6v
DO NOT EVER touch the leads together on a LiPo pack. Make sure the charging leads are connected properly. Connecting positive to negative and negative to positive can cause a major fire. This includes the balance taps. Immediate and permanent damage will occur and can cause fires, explosions and other catastrophic failure.
Charging LiPo's:
Charge according to manufacturer directions. Most recommend 1C charge. This is calculated like above.
Example of a 5000mAh LiPo battery (5000mAh * 1C * .001 = 5A maximum charge current)
Never charge LiPo batteries over 4.2 volts per cell.
LiPo battery packs with multiple cells can become unbalanced. If this is the case, some cells can become overcharged and explode.To prevent unbalanced packs they should be charged with a balance charger about every fifth charge.
Balance Taps are different between brands and must be matched or a proper adapter used. This is not just because of the size and shape of the connector but because of the way the leads are connected to individual cells within the pack. Using the wrong connectors can cause major problems.
Here is a link to a chart about Balance Tap Compatibility.
ONLY CHARGE LIPO BATTERIES WITH A LIPO CHARGER
Charging a lipo battery with a charger designed for other batteries will cause problems, and will probably result in a fire. The battery manual will state the proper charging rates and times.
Don’t charge batteries unsupervised. Even when you do everything right, incidents can occur. Also, do not charge lithium polymer batteries in your car. A flame out can be disastrous if it occurs inside a vehicle.
It’s really important to charge lithium polymer batteries on a flame proof surface such as concrete. In the event of a fire, a fire proof charging surface will stop it from spreading, or at least slow it down significantly. The best protection while charging your lithium polymer batteries in a flame proof LipoSack or a crock to contain a fire if it should it occur. It could mean the difference between a minor clean up and the loss of your house or car. Also make sure that the storage area is well ventilated. If a fire does occur, you don’t want to be running around looking for something to put it out with. Water will not help put out a lipo fire. Being a conductor, it will cause a short circuit and could even make the fire worse. Use a type C fire extinguisher.
When you are uncertain of what to do:
Read the manual – The importance of reading your battery and chargers manual cannot be emphasized enough.
I'm sure I missed something so please do some more looking for info and read your instruction manuals."
"LiPo battery packs guide and warnings
First off LiPo batteries are fantastic if taken care of properly. The power to size and weight ratio is what makes these so desirable. Just a bit of info to help with LiPo selection and usage.
Discharging LiPo Batteries:
Limit LiPo Discharge to Rate or potential hazard happens when lithium polymer batteries are discharged too fast. If they do so they could potentially catch fire and burst. LiPo batteries are rated with a continuous and max discharge rating.
For example a 1500mAh LiPo may be rated at 10C continuous current should not be discharged at more than 1500mAh (1500mA * 10C * .001 = 15A) of current.
Many Lipo Packs also have a "Burst" rating. For a brief period of time you can draw more current from many LiPo packs. This "Burst" current is usually limited for around 10 seconds. The current is calculated the same way.
Another example would be a 5000mAh Lipo rated at 35C continuous current and burst of 50C for 10 seconds.
(5000mAh *35C * .001 = 175A continuous draw)
(5000mAh *50C * .001 = 250A draw for 10 seconds)
LiPo Minimum Voltage:
A very important consideration is to NOT allow the battery voltage to drop too low. The amount that the battery voltage can drop is dependent on your system. If you are using a 3-cell lithium polymer pack, you should stop use of it when voltage drops under 9 volts. If the battery voltage drops below 8 volts the batteries could become permanently damaged. Follow manufacturers recommended guidelines.
If this is unknown, a good rule to use is 3V per cell.
LiPo Maximum Temperature:
Lithium polymer batteries should not be operated in temperatures exceeding 140 degrees Fahrenheit. In the event of a crash, lithium polymer batteries should be carefully inspected for any punctures, puffiness of the batteries, or short circuits. If any of exists, do not use the batteries. Dispose of them properly. Also, NEVER store / charge lithium polymer batteries in your car – Unless you hate your car. Batteries can and do explode, and if this happens inside a vehicle the result is usually catastrophic. On a hot day, temperatures can rise inside the car and cause stored packs to rupture.
Damaged LiPo Symptoms:
• Charger does not allow the battery to charge
• Batteries are puffy to the touch (do not use!)
• Punctures in the battery cell
• Short circuits
Properly LiPo Dispose Procedure:
• Discharge all cells to the recommend cut off voltage of 3 Volts per cell
• Place in salt water for several hours
• Apply tape to one of the terminals and dispose of in the trash.
• DO NOT INCINERATE
Parallel Battery Configuration:
Use Equally Charged LiPo’s in Parallel Configurations. Battery configurations require the parallel connection of two or more Lithium Polymer (LiPo) batteries. In this case, LiPo batteries must have the same or very similar output voltage. WARNING Parallel connection of two batteries of significantly different output voltage (one is more fully charged than the other) will cause one battery to discharge into the other battery at a high current rate. This may cause damage to either of the batteries and potentially cause fire or the battery to burst. It is strongly recommended that in applications requiring parallel connection of LiPo batteries, only batteries of equivalent technology, capacity, cell count, and output voltage be used. A good assumption is that fully charged LiPo batteries of the same type are safe to connect in parallel. Unless you are certain of the proper way to connect batteries in Series or Parallel, NEVER CONNECT LIPO PACKS TOGETHER.
LiPo Cell configuration:
There are several styles, sizes and combination that are available. Most are found in a series or series parallel configuration. What ever the configuration the # of cells * 3.7v per cell = Pack voltage
Example a 3S (3 cell) * 3.7v per cell = 11.1 volts
1s= 3.7v
2s= 7.4v
3s= 11.1v
4s= 14.8v
5s= 18.5v
6s= 22.2v
7s= 25.9v
8s= 29.6v
DO NOT EVER touch the leads together on a LiPo pack. Make sure the charging leads are connected properly. Connecting positive to negative and negative to positive can cause a major fire. This includes the balance taps. Immediate and permanent damage will occur and can cause fires, explosions and other catastrophic failure.
Charging LiPo's:
Charge according to manufacturer directions. Most recommend 1C charge. This is calculated like above.
Example of a 5000mAh LiPo battery (5000mAh * 1C * .001 = 5A maximum charge current)
Never charge LiPo batteries over 4.2 volts per cell.
LiPo battery packs with multiple cells can become unbalanced. If this is the case, some cells can become overcharged and explode.To prevent unbalanced packs they should be charged with a balance charger about every fifth charge.
Balance Taps are different between brands and must be matched or a proper adapter used. This is not just because of the size and shape of the connector but because of the way the leads are connected to individual cells within the pack. Using the wrong connectors can cause major problems.
Here is a link to a chart about Balance Tap Compatibility.
ONLY CHARGE LIPO BATTERIES WITH A LIPO CHARGER
Charging a lipo battery with a charger designed for other batteries will cause problems, and will probably result in a fire. The battery manual will state the proper charging rates and times.
Don’t charge batteries unsupervised. Even when you do everything right, incidents can occur. Also, do not charge lithium polymer batteries in your car. A flame out can be disastrous if it occurs inside a vehicle.
It’s really important to charge lithium polymer batteries on a flame proof surface such as concrete. In the event of a fire, a fire proof charging surface will stop it from spreading, or at least slow it down significantly. The best protection while charging your lithium polymer batteries in a flame proof LipoSack or a crock to contain a fire if it should it occur. It could mean the difference between a minor clean up and the loss of your house or car. Also make sure that the storage area is well ventilated. If a fire does occur, you don’t want to be running around looking for something to put it out with. Water will not help put out a lipo fire. Being a conductor, it will cause a short circuit and could even make the fire worse. Use a type C fire extinguisher.
When you are uncertain of what to do:
Read the manual – The importance of reading your battery and chargers manual cannot be emphasized enough.
I'm sure I missed something so please do some more looking for info and read your instruction manuals."
11-10-2009, 08:30 PM
#38
Senior Member
RE: Damnit, the lipo battery industry needs better standards!
ORIGINAL: Fade2Black1
Thats why I said :
But, Not all lipo's can be charged at a 1c rate. my 240mah Hyperions can be charged at 5c which is 1.2amp, states it right on the package. Do I? did a few 1amp charges outside on the concreate. No problems thus far, but I usually charge them at 1c or .24
But also I have seen a lipo go boom on a triton that only allows a 1c charge and will cut at a high voltage reading or the mah set..
The inherant danger of lipo's scare me... I dont like flames.
ORIGINAL: black mamba
I'll come out and say it-Lipos are really only as safe as the people using or charging them. The easiest way to start a fire is to overcharge/improperly charge them. Next easiest way is to short them when soldering on connectors or puncturing the pack for whatever reason. How to avoid this stuff? Get a lipo charger that has a auto mode or input verification mode-most all do now. That way you cannot overcharge or improperly charge them. If you don't have one of these chargers, always double check your inputs...make sure your pack info you have entered into the charger is right for the packs you are charging. Additionally, you should charge at 1A per 1000mah of battery capacity. That means 4.0A for a 4000mah pack, 3.5A for a 3500mah pack. As far as shorting and punctures, treat your lipos with more respect than say your typical nimh stick pack and pay attention when soldering on connectors-don't let the pos and neg wires touch. You could also run hardcased lipos because they are a bit more durable than soft cased lipos. With that said, I have hundreds of lipo cycles under my belt without any issues whatsoever and plan on hundreds more without any issues. Just folllow the ''rules'' of lipo and you'll be ok.
I'll come out and say it-Lipos are really only as safe as the people using or charging them. The easiest way to start a fire is to overcharge/improperly charge them. Next easiest way is to short them when soldering on connectors or puncturing the pack for whatever reason. How to avoid this stuff? Get a lipo charger that has a auto mode or input verification mode-most all do now. That way you cannot overcharge or improperly charge them. If you don't have one of these chargers, always double check your inputs...make sure your pack info you have entered into the charger is right for the packs you are charging. Additionally, you should charge at 1A per 1000mah of battery capacity. That means 4.0A for a 4000mah pack, 3.5A for a 3500mah pack. As far as shorting and punctures, treat your lipos with more respect than say your typical nimh stick pack and pay attention when soldering on connectors-don't let the pos and neg wires touch. You could also run hardcased lipos because they are a bit more durable than soft cased lipos. With that said, I have hundreds of lipo cycles under my belt without any issues whatsoever and plan on hundreds more without any issues. Just folllow the ''rules'' of lipo and you'll be ok.
I just rather not take the chance of making a mistake
But also I have seen a lipo go boom on a triton that only allows a 1c charge and will cut at a high voltage reading or the mah set..
The inherant danger of lipo's scare me... I dont like flames.
11-11-2009, 12:26 AM
#39
Senior Member
RE: Damnit, the lipo battery industry needs better standards!
ORIGINAL: black mamba
Why would you even run a Flux on nimh? That'd be like running diesel fuel in your gasoline burning engine. 2S should be the minimum pack run in a Flux. It would take more than a LRP to hang with a Flux on 2S. On 3S, well, it would take one very stout nitro engine to hang with it.
ORIGINAL: HerrSavage
Just curious - everybody knows a well running lipo brushless is faster than nitro..
Take, say, a Savage XL with LRP Spec 3, and put it up against a Flux with Nimh. How would they compare?
Just curious..
Just curious - everybody knows a well running lipo brushless is faster than nitro..
Take, say, a Savage XL with LRP Spec 3, and put it up against a Flux with Nimh. How would they compare?
Just curious..
That doesn't answer my question.
11-11-2009, 12:48 AM
#40
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RE: Damnit, the lipo battery industry needs better standards!
ORIGINAL: HerrSavage
That doesn't answer my question.
ORIGINAL: black mamba
Why would you even run a Flux on nimh? That'd be like running diesel fuel in your gasoline burning engine. 2S should be the minimum pack run in a Flux. It would take more than a LRP to hang with a Flux on 2S. On 3S, well, it would take one very stout nitro engine to hang with it.
ORIGINAL: HerrSavage
Just curious - everybody knows a well running lipo brushless is faster than nitro..
Take, say, a Savage XL with LRP Spec 3, and put it up against a Flux with Nimh. How would they compare?
Just curious..
Just curious - everybody knows a well running lipo brushless is faster than nitro..
Take, say, a Savage XL with LRP Spec 3, and put it up against a Flux with Nimh. How would they compare?
Just curious..
That doesn't answer my question.
11-11-2009, 12:54 AM
#42
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RE: Damnit, the lipo battery industry needs better standards!
ORIGINAL: HerrSavage
'K, thanks.. As I said, was just curious..
'K, thanks.. As I said, was just curious..
11-11-2009, 01:03 AM
#43
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RE: Damnit, the lipo battery industry needs better standards!
ORIGINAL: IceWindius
once a Flux is powered by 4S, most nitro's can't keep up and on 6S none of them can.
once a Flux is powered by 4S, most nitro's can't keep up and on 6S none of them can.
11-11-2009, 01:13 AM
#44
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RE: Damnit, the lipo battery industry needs better standards!
ORIGINAL: HPI_Savage_RC
Until the drivetrain explodes...
ORIGINAL: IceWindius
once a Flux is powered by 4S, most nitro's can't keep up and on 6S none of them can.
once a Flux is powered by 4S, most nitro's can't keep up and on 6S none of them can.
11-11-2009, 01:50 AM
#45
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RE: Damnit, the lipo battery industry needs better standards!
My point is that 6s will annihilate a Savage drivetrain. I've seen people snap outdrives, driveshaft pins, driveshafts, wear down transmission gears to nothing in a matter of a few minutes, etc. If you want the drivetrain to stay together for long, you can't really run more power than what a strong Nitro engine provides, so all performance comparisons are moot.
11-11-2009, 10:40 AM
#46
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RE: Damnit, the lipo battery industry needs better standards!
I already said this in another thread, but, LiPos are everywhere. Due to the advantages in shape (Li-ion had to always be cylindrical), they have been slowly replacing Li-ion in your more common consumer devices. iPods, PSPs, some of the newer laptop batteries, just about every new cellphone battery, the battery that goes into your digital camera, etc. They're out there. Be afraid, be very afraid... 
11-11-2009, 11:14 AM
#47
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RE: Damnit, the lipo battery industry needs better standards!
What has this to do with the original topic?
ORIGINAL: HPI_Savage_RC
My point is that 6s will annihilate a Savage drivetrain. I've seen people snap outdrives, driveshaft pins, driveshafts, wear down transmission gears to nothing in a matter of a few minutes, etc. If you want the drivetrain to stay together for long, you can't really run more power than what a strong Nitro engine provides, so all performance comparisons are moot.
My point is that 6s will annihilate a Savage drivetrain. I've seen people snap outdrives, driveshaft pins, driveshafts, wear down transmission gears to nothing in a matter of a few minutes, etc. If you want the drivetrain to stay together for long, you can't really run more power than what a strong Nitro engine provides, so all performance comparisons are moot.
11-11-2009, 11:51 AM
#49
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RE: Damnit, the lipo battery industry needs better standards!
ORIGINAL: HPI_Savage_RC
Until the drivetrain explodes...
ORIGINAL: IceWindius
once a Flux is powered by 4S, most nitro's can't keep up and on 6S none of them can.
once a Flux is powered by 4S, most nitro's can't keep up and on 6S none of them can.
11-11-2009, 12:14 PM
#50
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RE: Damnit, the lipo battery industry needs better standards!
ORIGINAL: HPI_Savage_RC
My point is that 6s will annihilate a Savage drivetrain. I've seen people snap outdrives, driveshaft pins, driveshafts, wear down transmission gears to nothing in a matter of a few minutes, etc. If you want the drivetrain to stay together for long, you can't really run more power than what a strong Nitro engine provides, so all performance comparisons are moot.
My point is that 6s will annihilate a Savage drivetrain. I've seen people snap outdrives, driveshaft pins, driveshafts, wear down transmission gears to nothing in a matter of a few minutes, etc. If you want the drivetrain to stay together for long, you can't really run more power than what a strong Nitro engine provides, so all performance comparisons are moot.
Nitro, in my opinion, is so much more fun and exciting! Electric cars are quiet and boring. Idon't dispute their speed, Ijust think they are boring. I was tired of RC until Igot hooked all over again.......by Nitro!